在冷喷涂（CS）的沉积过程中，颗粒间结合强度较弱，涂层内普遍存在孔隙和颗粒间边界等缺陷。为研究这些缺陷的形成机制，在不同载流温度下，制备了3种不同粒度分布的Ti金属涂层；根据试验参数，建立随机多颗粒沉积的Coupled Euler-Lagrange （CEL）模型，计算获得了颗粒沉积后的变形情况及涂层内部的孔隙分布规律。结果表明，数值模拟和试验结果吻合良好。碰撞作用导致颗粒的累积呈现方向性，随着速度提高，颗粒的变形增大且内层颗粒受速度影响比外层颗粒更大。在相同参数下，大粒径颗粒沉积获得孔隙尺寸更大，孔隙率更高。在低速情况下，涂层内部的孔隙会相互连通形成孔簇，而随着临界速度比增大，孔隙率降低。

In the deposition process of Cold Spraying （CS）， the bonding strength between particles is small， and defectsas pores and interparticle boundaries are common in the coatings. In order to study the formation mechanism of these defects， three kinds of Ti coatings with different particle sizes distributions were prepared at different airflow temperatures. According to the experimental parameters， the Coupled Euler-Lagrange （CEL） model of random multi-particle deposition was established， and the deformation of particles after deposition and the pores distribution law inside the coatings were calculated. The results showed that the numerical simulation and experimental results were in good agreement. The collision action causes the accumulation of particles to be directional， and with the increase of velocities， the deformation of particles increases， and the inner particles are more affected by the velocities than the outer particles. Under the same parameters， the deposits with large particles have larger pores and higher porosities. At low velocities， the pores inside the coatings communicate with each other to form pore clusters， and as the velocities increase， the pore sizes decrease and the porosities decrease.